Added Fast PS

When enabled:
When tuning to a new station PS is shown immediately. After two complete PS cycles normal PS detection is activated. This can cause incompete or faulty PS direct after tuning, which will recover.

Disabled:
After two complete PS cycles the PS is shown. This can take some longer time to show PS but will prevent errors as much as possible.

In previous builds fast PS was already enabled, but can now be disabled if wanted.

Also a small fix: when RDS is lost and level drops below low level threshold, the textcolor was not changed.

src/constants.h

@@ -108,7 +108,7 @@
 #define EE_PRESETS_CNT              99
 #define EE_CHECKBYTE_VALUE          34 // 0 ~ 255,add new entry, change for new value 
 
-#define EE_TOTAL_CNT                617
+#define EE_TOTAL_CNT                618
 #define EE_UINT16_FREQUENCY_FM      0
 #define EE_BYTE_VOLSET              4
 #define EE_BYTE_STEREO              5
@@ -180,12 +180,11 @@
 #define EE_INT16_AMLEVELOFFSET      98
 #define EE_UINT16_FREQUENCY_OIRT    102
 #define EE_STRING_XDRGTK_KEY        106  // 11 byte
-#define EE_PRESETS_BAND_START       118
-#define EE_PRESETS_START            220
+#define EE_BYTE_FASTPS              118
+#define EE_PRESETS_BAND_START       119
+#define EE_PRESETS_START            221
 #define EE_PRESETS_FREQUENCY        8750
 
-
-
 // End of EEPROM index defines
 
 static const char* const unitString[] = {"dBμV", "dBf", "dBm"};