tzselect: Fix for gawk treating '\.' as plain '.'

When using gawk and Posix TZ in tzselect, this warning is shown:
	awk: cmd. line:1: warning: escape sequence `\.' treated as plain `.'
gawk treats '\.' as '.'
mawk treats '\.' as '\.'
both treat '\\.' as '\\.'
The 2nd and 3rd are corrrect for 'Mm.w.d'.

Test:
gawk 'BEGIN{ date = "\."; print date }'
gawk 'BEGIN{ date = "\\."; print date }'
versus:
mawk 'BEGIN{ date = "\."; print date }'
mawk 'BEGIN{ date = "\\."; print date }'
* tzselect.ksh (date): Fix bug that broke POSIX TZ checking with gawk.
* NEWS: Document this.
Adjust pre-1940 Iceland data to match the Iceland Almanak.

* europe (Iceland, Atlantic/Reykjavik):
Correct entries for 1939, 1921, 1919, and 1837-1907.
Coalesce some other entries, for simplicity.
* NEWS: Document this.
* NEWS: Fix misspelling.  (Thanks to Chris Rorvick.)
* europe (Iceland): Typo fix in commentary.
tzselect: Removed spaces in calls to awk-functions

Explanation:
GNU awk fails when a user-defined-functions is called with a space like in
'myUDF ()'. It does not fail when calling builtin functions, but removed
those spaces too.

Example code:
good_awk='function echo(x) { return x; } BEGIN { print echo("x"); }'
bad_awk_='function echo(x) { return x; } BEGIN { print echo ("x"); }'
sin_awk='BEGIN { print sin (0) }'

mawk -W version 2>/dev/null | head -n1
mawk "${sin_awk}"
mawk "${good_awk}"
mawk "${bad_awk_}"
gawk -V | head -n1
gawk "${sin_awk}"
gawk "${good_awk}"
gawk "${bad_awk_}"

Output:
mawk 1.3.4 20141027
0
x
x
GNU Awk 4.0.2
0
x
gawk: cmd. line:1: error: function `echo' called with space between name
and `(',
* NEWS: Document POSIX awk fixes.
Move out-of-scope Arabian peninsula zones to 'backzone'.

* asia (Asia/Bahrain): Now links to Asia/Qatar.
(Asia/Kuwait, Asia/Aden): Now links to Asia/Riyadh.
(Asia/Muscat): Now links to Asia/Dubai.
* backzone: Move the old data here.
* checktab.awk (tztab): Remove special cases for these zones.
* NEWS: Document the above.