Avoid sbt-web 1.4.x dependency, use latest 1.5.x

[mkurz]

The "problem" is that currently sbt-web 1.4.x is pulled in, but only sbt-web 1.5.+ is hosted on maven central. So when blocking the deprecated repos, I can not build the project:

[warn]  Note: Some unresolved dependencies have extra attributes.  Check that these dependencies exist with the requested attributes.
[warn]          com.typesafe.sbt:sbt-web:1.4.4 (scalaVersion=2.12, sbtVersion=1.0)
[warn] 
[warn]  Note: Unresolved dependencies path:
[error] sbt.librarymanagement.ResolveException: Error downloading com.typesafe.sbt:sbt-web;sbtVersion=1.0;scalaVersion=2.12:1.4.4
[error]   Not found
[error]   Not found
[error]   not found: https://repo1.maven.org/maven2/com/typesafe/sbt/sbt-web_2.12_1.0/1.4.4/sbt-web-1.4.4.pom
[error]   not found: /home/mkurz/.ivy2/local/com.typesafe.sbt/sbt-web/scala_2.12/sbt_1.0/1.4.4/ivys/ivy.xml
[error]   download error: Caught java.net.ConnectException (Connection refused (Connection refused)) while downloading https://repo.scala-sbt.org/scalasbt/sbt-plugin-releases/com.typesafe.sbt/sbt-web/scala_2.12/sbt_1.0/1.4.4/ivys/ivy.xml
[error]   download error: Caught java.net.ConnectException (Connection refused (Connection refused)) while downloading https://repo.typesafe.com/typesafe/ivy-releases/com.typesafe.sbt/sbt-web/scala_2.12/sbt_1.0/1.4.4/ivys/ivy.xml
...
[error] (update) sbt.librarymanagement.ResolveException: Error downloading com.typesafe.sbt:sbt-web;sbtVersion=1.0;scalaVersion=2.12:1.4.4
[error]   Not found
[error]   Not found
[error]   not found: https://repo1.maven.org/maven2/com/typesafe/sbt/sbt-web_2.12_1.0/1.4.4/sbt-web-1.4.4.pom
[error]   not found: /home/mkurz/.ivy2/local/com.typesafe.sbt/sbt-web/scala_2.12/sbt_1.0/1.4.4/ivys/ivy.xml
[error]   download error: Caught java.net.ConnectException (Connection refused (Connection refused)) while downloading https://repo.scala-sbt.org/scalasbt/sbt-plugin-releases/com.typesafe.sbt/sbt-web/scala_2.12/sbt_1.0/1.4.4/ivys/ivy.xml
[error]   download error: Caught java.net.ConnectException (Connection refused (Connection refused)) while downloading https://repo.typesafe.com/typesafe/ivy-releases/com.typesafe.sbt/sbt-web/scala_2.12/sbt_1.0/1.4.4/ivys/ivy.xml

dependency tree build.sbt:

[info] com.github.sbt:sbt-paradox-material-theme:0.6.0-SNAPSHOT
[info]   +-com.lightbend.paradox:sbt-paradox:0.9.2
[info]     |
[info]     +-com.typesafe.sbt:sbt-web:1.4.4

dependency tree project/plugins.sbt:

[info] default:project:0.1.0-SNAPSHOT
[info]   +-com.lightbend.paradox:sbt-paradox-theme:0.9.2
[info]   | +-com.typesafe.sbt:sbt-web:1.4.4
[info]   |
[info]   +-com.lightbend.paradox:sbt-paradox:0.9.2
[info]     |
[info]     +-com.typesafe.sbt:sbt-web:1.4.4

sbt-web was upgraded to 1.5.x just recently in paradox 0.10.6: lightbend/paradox@80c9c01

However because we want to use paradox 0.9.2 for a 0.7.0 release, it makes sense to override the used sbt-web version to use 1.5.x. Since I maintain sbt-web I can pretty much assure that 1.4.x and 1.5.x are compatible, however the only thing I removed where the Compat objects, because sbt 1.5.x does not cross compile to sbt 0.13.x anymore. This was not a problem until now, because I always just changed Compat.cacheStore(streams.value, "...") to streams.value.cacheStoreFactory.make("...") in all the projects I migrated to sbt-web 1.5.x.

This PR now fails however because of course paradox 0.9.x still uses that Compat object's methods:

[info] [error] java.lang.NoClassDefFoundError: com/typesafe/sbt/web/Compat$
...
[info] [error] Caused by: java.lang.ClassNotFoundException: com.typesafe.sbt.web.Compat$

So we have three choices:

1. Do not upgrade to sbt-web 1.5.x but stay on 1.4.x and fetch it from the deprecated repo.
   I am against that, because bumping sbt-web 1.4.x to 1.5.x never caused any problems in other projects and sbt 1.5.x did fix problems, like memory leaks, got ride of the akka dependency within sbt (which was a bit... not nice to do that), support for newever npm/node versions etc.
2. Ask lightbend (again) to release paradox 0.9.3 which avoids using the Compat object, so we can bump to sbt 1.5.x here. However I guarantee you this will never happen. Lightbend does not do that, we asked different things in the last two years to fix for us (like backport the Scala 3 support PR to akka-http 10.2.x, which would not be hard, they didn't do it).
3. I will just re-add the Compat object to a new sbt-web 1.5.4 release so this PR turns green. IMHO this is the easiest thing to do and also a manageable trade off.

[mkurz]

Re-introduced the Compat object:

• Re add Compat#cacheStore sbt-web#226

released as sbt-web 1.5.4.