Track version number for next release in file

Only major and minor version numbers. Patch numbers remains calculated.

The trick to get current directory only works in Bash or Zsh. See:
https://stackoverflow.com/questions/9901210/bash-source0-equivalent-in-zsh#54755784

Note that "$0" won't work since the script is sourced, not executed.

Tools/utils.sh

@@ -22,16 +22,9 @@ function get_short_version() {
     if [ $COMMIT_COUNT_SINCE_TAG = 0 ]; then
         SHORT_VERSION="$LATEST_TAG"
     else
-        # increment final digit of tag and append "d" + commit-count-since-tag
-        # e.g. commit after 1.0 is 1.1d1, commit after 1.0.0 is 1.0.1d1
-        # this is the bit that requires /bin/bash
-        OLD_IFS=$IFS
-        IFS="."
-        VERSION_PARTS=($LATEST_TAG)
-        LAST_PART=$((${#VERSION_PARTS[@]}-1))
-        VERSION_PARTS[$LAST_PART]=$((${VERSION_PARTS[${LAST_PART}]}+1))
-        SHORT_VERSION="${VERSION_PARTS[*]}d${COMMIT_COUNT_SINCE_TAG}"
-        IFS=$OLD_IFS
+        local tools_dir=$(dirname "${BASH_SOURCE[0]:-${(%):-%x}}")
+        local next_version=$(cat "$tools_dir/version.txt")
+        SHORT_VERSION="${next_version}d${COMMIT_COUNT_SINCE_TAG}"
     fi
     echo $SHORT_VERSION
 }

Tools/version.txt

@@ -0,0 +1 @@
+0.8.0