Fix many typos in docs and comments

This commit corrects many typos found in scaladocs, comments and
documentation. It should reduce a bit number of PRs which fix one
typo.

There are no changes in the 'real' code except one corrected name of
a JUnit test method and some error messages in exceptions. In the case
of typos in other method or field names etc., I just skipped them.

Obviously this commit doesn't fix all existing typos. I just generated
in IntelliJ the list of potential typos and looked through it quickly.

1 files changed, 1 insertions, 1 deletions

diff --git a/test/files/run/t5313.scala b/test/files/run/t5313.scala
index 0d7168fa89..7f5af74c3f 100644
--- a/test/files/run/t5313.scala
+++ b/test/files/run/t5313.scala
@@ -11,7 +11,7 @@ object Test extends IcodeComparison {
       def bar = {
         var kept1 = new Object
         val result = new java.lang.ref.WeakReference(kept1)
-        kept1 = null // we can't eliminate this assigment because result can observe
+        kept1 = null // we can't eliminate this assignment because result can observe
                    // when the object has no more references. See SI-5313
         kept1 = new Object // but we can eliminate this one because kept1 has already been clobbered
         var erased2 = null // we can eliminate this store because it's never used